Bulked yarns



United States Patent 3,470,684 BULKED YARNS Anil Chandrakant Parikh, Caerleon, and Barrie Daniels, Cwmbran, England, assignors to British Nylon Spinners Limited, Pontypool, Monmouthsllire, England No Drawing. Filed Oct. 29, 1964, Ser. No. 407,535 Claims priority, application Great Britain, Oct. 30, 1963. 42,727/63 Int. 'Cl. D02g 3/02; D01h 1/00; D04h 17/00 US. Cl. 57140 5 Claims ABSTRACT OF THE DISCLOSURE A composite bulked yarn of continuous synthetic filaments contained in a plurality of singles yarns and wherein the filaments have stable crimped configurations characterized by the fact that the singles yarns are closely interconnected by virtue of said crimped configurations and of a low degree of set folding twist, said configurations being superimposed on said folding twist.

The invention concerns improvements in or relating to bulked yarns.

Bulked yarns of continuous filamentary synthetic polymer material are now used in the textile industry for a wide range of products. Such bulked yarns can be made in a variety of ways, all of them involving the disarrangement of the straight, parallel relationship of the filaments. Mechanical crimping, concurrently with heat-setting, and sometimes followed by crimp development treatments is the most usual way of producing these bulked yarns; and there are sundry such mechanical crimping methods, as, for example, false twist crimping, edge crimping, stuffer box crimping and gear crimping.

Where heavy denier bulked yarns are required, as in the manufacture of carpets and the like, and in some upholstery fabrics and blankets, bed-covers and similar household textiles, it is sometimes preferred, as a practical matter, to make up the required total denier by combining a plurality of yarns prior to mechanical crimping.

If such composite bulked yarns are required for use as, for instance, the pile yarns in cut-pile tufted fabrics, it is necessary, when the tufts are desired to retain their individuality in appearance, that a low degree of folding twist shall have been applied thereto and the twist set. Up to now, the folding twist has been applied after crimping and the setting of the folding twist carried out in a separate process, although such setting may itself be combined with dyeing of the yarn.

In general, however, it is preferred to piece-dye pile fabrics; and when such piece-dyeing is carried out, whatever fold-in twist may have been inserted after crimping will be lost if it has not been set in a separate process carried out on the yarn.

We have now discovered that the desired appearance of the tufts can be afforded, and, indeed, a more coherent yarn obtained by using composite bulked yarns comprising a plurality of singles yarns which have been folded with a low degree of folding twist which has been set at the time of crimping.

The present invention therefore comprises a composite bulked yarn of continuous filaments of synthetic polymer material wherein the filaments are contained in a plurality of singles yarns and wherein the filaments have stable crimped configurations and the singles yarns are closely interconnected by virtue of said crimped configurations "Ice and of a low degree of set folding twist, said configurations being superimposed on said folding twist.

Preferably, the crimped configurations of the filaments are produced by compression crimping, as in a stufferbox process; and the crimped configurations are rendered stable and the folding twist is set by the setting treatment that occurs concurrently or consecutively with the crimping process. The crimps may, however, be imparted in other ways, as for example by gear crimping, false-twist crimping or edge crimping.

A low folding twist of some 3-5 turns per inch is often sufiicient, e.g., with three 1,000 denier multifilament yarns of polyhexamethylene adipamide destined for use in cutpile tufted carpets. In such a use, the yarns of the invention donate adequate tuft definition to the cut tufts. This is not the case with bulked yarns, comprising a plurality of crimped singles yarns, when such bulked yarns have been twisted or otherwise combined after the crimping treatment, and that twist has not been specifically set in a separate process or in a yarn-dyeing process. Even in the latter case, i.e., when the twist has been. subsequently set, the yarn is not such a compact entity as the yarn of the invention, owing to the fact that the crimp has not been superimposed on the folding twist.

One example of the invention consists of a composite bulked yarn of three singles yarns each of 1,040 denier/ 68 filament polyhexamethylene adipamide, the filaments of which have the generally zig-zag crimp characteristic of stuffer-box crimping, and the singles yarns of which are compactly united by said crimps and by a set folding twist of 3 turns per inch upon which said crimps are superimposed.

Such yarn was made by folding the singles supply yarns, forwarding the folded composite yarn to a stufferbox crimper by means of a forwarding roll driven by the periphery of one of the stufier-box nip rolls crimping in said stuffer-box and heat-setting the crimped composite yarn in the setting chamber portion thereof at C., withdrawing said crimped and set composite yarn from the setting chamber at a controlled tension, and winding the yarn into a package.

What we claim is:

1. A composite bulked yarn of continuous filaments of synthetic poly material wherein the filaments are contained in a plurality of singles yarns and wherein the filaments have stable crimped configurations characterised by the fact that the singles yarns are closely interconnected by virtue of said crimped configurations and of a low degree of set folding twist, said configurations being superimposed on said folding twist.

2. A composite bulked yarn according to claim 1 in which the crimped configurations are of a generally zigzag nature.

3. A composite bulked yarn according to claim 1 in which the folding twist is from about 3-5 turns per inch.

4. A process for making a composite bulked yarn comprising the steps of:

(a) applying a low folding twist to a plurality of singles multifilament yarns of synthetic polymer material,

(b) forwarding the folded composite yarn to a crimping mechanism,

(c) crimping the folded composite yarn thereby to superimpose crimped configurations on said folding twist, and

(d) heat-setting the yarn to set the crimp and the folding twist.

9 4 u 5. A process according to claim 4 in which a folding 3,009,233 11/1961 Murchie et a1 28-72 twist of 3-5 turns per inch is applied to three singles 3,147,533 9/1964 Baer 281 yarns, 3,238,591 3/1966 Rosenstein 281 References Cited 3,256,582 6/1966 Burleson 281 UNITED STATES PATENTS 5 JOHN PETRAKES, Primary Examiner 2,715,309 8/1955 Rosenstein et a1. 57140 CL XR.

2,972,798 2/1961 Stanley et a1 28-72 28 72; 57 157 

